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dispatcherTimer not restarting

I'm implementing a countdown in my app
private async void Window_Activated(object sender, WindowActivatedEventArgs args)
{
dispatcherTimer = new DispatcherTimer();
dispatcherTimer.Tick += dispatcherTimer_Tick;
dispatcherTimer.Interval = new TimeSpan(0,1,0);
dispatcherTimer.Start();
}
private void dispatcherTimer_Tick(object sender, object e)
{
TimeSpan timeSpan = new TimeSpan(blockTime.Hours, blockTime.Minutes, blockTime.Seconds);
if (timeSpan != TimeSpan.Zero)
{
timeSpan = timeSpan.Subtract(TimeSpan.FromMinutes(1));
Countdown_TexBlock.Text = String.Format("{0}:{1}", timeSpan.Hours, timeSpan.Minutes);
dispatcherTimer.Start();
}
else
{
dispatcherTimer.Stop();
}
}
The code works but only one time
For example I put 15 minutes in the blocktime (the time that the countdown will be running)
after a minute the countdown.text would be 0:14.
So only works after the first minute
Is not supposed to be restarted with dispatcher.start()

In the code that you posted, I don't see the blockTime variable being changed to any other value than it has in the beginning. This means that on every tick of dispatchTimer the value of the timeSpan.Subtract expression will always evaluate to the same 14 minutes. In your code, that 14 minutes is assigned to a local vaiable that is disposed when the tick is over. This gives the appearance that the dispatchTimer has stopped issuing Tick when it hasn't.
Here's what I ran that works as expected (for testing, I changed the minutes to seconds to make it observable in a reasonable time).
public sealed partial class MainWindow : Window
{
public MainWindow()
{
this.InitializeComponent();
// Create the dispatch timer ONCE
dispatcherTimer = new DispatcherTimer();
dispatcherTimer.Tick += DispatcherTimer_Tick;
dispatcherTimer.Interval = TimeSpan.FromSeconds(1);
// This will restart the timer every
// time the window is activated
this.Activated += (sender, e) =>
{
startOrRestartDispatchTimer();
};
}
private void startOrRestartDispatchTimer()
{
dispatcherTimer.Stop(); // If already running
blockTime = TimeSpan.FromSeconds(15);
Countdown_TexBlock.Text = blockTime.ToString();
dispatcherTimer.Start();
}
private void DispatcherTimer_Tick(object sender, object e)
{
if (blockTime > TimeSpan.Zero)
{
blockTime = blockTime.Subtract(TimeSpan.FromSeconds(1));
Countdown_TexBlock.Text = blockTime.ToString();
if (blockTime == TimeSpan.Zero)
{
Countdown_TexBlock.Text = "Done";
dispatcherTimer.Stop();
}
}
}
TimeSpan blockTime = TimeSpan.FromSeconds(15);
private DispatcherTimer dispatcherTimer;
// This will restart the timer when the button is clicked.
private void buttonRestart_Click(object sender, RoutedEventArgs e) =>
startOrRestartDispatchTimer();
}

DispatcherTimer to run randomly in WPF

I need to do some stuff in my application while application is running. I put it in dispatcher to work withing given time intervals. But now I want to randomized things.
I want to set random time intervals.
dTSettings.Tick += new EventHandler(dTSettings_Tick);
dTSettings.Interval = new TimeSpan(0, SetRandomTimer(), 0);
dTSettings.Start();
how to do that?

private DispatcherTimer _timer = new DispatcherTimer();
private Random rand = new Random();
public void InitAndStartTimer()
{
_timer.Tick += dispatcherTimer_Tick;
_timer.Interval = TimeSpan.FromSeconds(rand.Next(1, 10)); // From 1 s to 10 s
_timer.Start();
}
private void dispatcherTimer_Tick(object sender, EventArgs e)
{
_timer.Interval = TimeSpan.FromSeconds(rand.Next(1, 10)); // From 1 s to 10 s
// Do your work.
}

Timer Implementation not Running every 5 seconds as intended c#

I have the following timer implementation. But the timer is not running every 5 seconds as needed. How can make this run every 5 seconds. At present its running about once in 30 seconds.
private void button1_Click(object sender, RoutedEventArgs e)
{
msgsent = 0;
timer.Tick += timer_Tick;
timer.Interval = new TimeSpan(0, 0, 5);
bool isenable = timer.IsEnabled;
timer.Start();
}
private async void timer_Tick(object sender, object e)
{
if (geo == null)
{
geo = new Geolocator();
}
Geoposition posi = await geo.GetGeopositionAsync();
if (posi.Coordinate.Point.Position.Latitude <= 12.9227 && posi.Coordinate.Point.Position.Longitude >= 080.1320)
{
if (msgsent <=1)
{
msgsent = msgsent + 1;
ShowDialog(new MessageDialog("Your Bus has crossed xyz"));
}
}
}

I'll give you a hint. If you understand where each goes, then it should be clear. If not, you will once you get better.
// in the class definition
int msgsent;
Timer timer;
and
// in the constructor
timer = new Timer();
timer.Tick += timer_Tick;
timer.Interval = new TimeSpan(0, 0, 5);
and
// in the Button.Click event handler
timer.Start();
and
// in the Timer.Tick event handler
timer.Stop();
/* do your work here */
timer.Start();
There will be further issues when the user is clicking the button while you're doing your work, but that's beyond the scope of this question.

Timer won't tick

I have a Windows.Forms.Timer in my code, that I am executing 3 times. However, the timer isn't calling the tick function at all.
private int count = 3;
private timer;
void Loopy(int times)
{
count = times;
timer = new Timer();
timer.Interval = 1000;
timer.Tick += new EventHandler(timer_Tick);
timer.Start();
}
void timer_Tick(object sender, EventArgs e)
{
count--;
if (count == 0) timer.Stop();
else
{
// Do something here
}
}
Loopy() is being called from other places in the code.

Try using System.Timers instead of Windows.Forms.Timer
void Loopy(int times)
{
count = times;
timer = new Timer(1000);
timer.Enabled = true;
timer.Elapsed += new ElapsedEventHandler(timer_Elapsed);
timer.Start();
}
void timer_Elapsed(object sender, ElapsedEventArgs e)
{
throw new NotImplementedException();
}

If the method Loopy() is called in a thread that is not the main UI thread, then the timer won't tick.
If you want to call this method from anywhere in the code then you need to check the InvokeRequired property. So your code should look like (assuming that the code is in a form):
private void Loopy(int times)
{
if (this.InvokeRequired)
{
this.Invoke((MethodInvoker)delegate
{
Loopy(times);
});
}
else
{
count = times;
timer = new Timer();
timer.Interval = 1000;
timer.Tick += new EventHandler(timer_Tick);
timer.Start();
}
}

I am not sure what you are doing wrong it looks correct, This code works: See how it compares to yours.
public partial class Form1 : Form
{
private int count = 3;
private Timer timer;
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
Loopy(count);
}
void Loopy(int times)
{
count = times;
timer = new Timer();
timer.Interval = 1000;
timer.Tick += new EventHandler(timer_Tick);
timer.Start();
}
void timer_Tick(object sender, EventArgs e)
{
count--;
if (count == 0) timer.Stop();
else
{
//
}
}
}

Here's an Rx ticker that works:
Observable.Interval(TimeSpan.FromSeconds(1))
.Take(3)
.Subscribe(x=>Console.WriteLine("tick"));
Of course, you can subscribe something more useful in your program.

you may have started the timer from another thread, so try invoking it from the correct thread.
for example, instead of:
timerX.start();
Use:
Invoke((MethodInvoker)delegate { timerX.Start(); });

Check if your timer in properties is enabled.
Mine was false and after setting to true it worked.

If you are using Windows.Forms.Timer then should use something like following.
//Declare Timer
private Timer _timer= new Timer();
void Loopy(int _time)
{
_timer.Interval = _time;
_timer.Enabled = true;
_timer.Tick += new EventHandler(timer_Elapsed);
_timer.Start();
}
void timer_Elapsed(object sender, EventArgs e)
{
//Do your stuffs here
}

If you use some delays smaller than the interval inside the timer, the system.timer will execute other thread and you have to deal with a double thread running at the same time. Apply an InvokeRequired to control the flow.

pausing a video after every 10s in c#

what i want to do is pause a video after every 10s
the video should pause after ever 10s till the video ends
the code given below gives unexpected results
the video pauses fine for the firs time (i.e after 10s)
but when i play again it should pause after 10s but in my case it pauses randomly sometimes at 8s,3s 5s and etc
what should i do??
please help
thanks!!
void PlayClick(object sender, EventArgs e)
{
VideoControl.Play();
var dispatcherTimer = new System.Windows.Threading.DispatcherTimer();
dispatcherTimer.Tick += new EventHandler(dispatcherTimer_Tick);
dispatcherTimer.Interval = new TimeSpan(0, 0, 10);
dispatcherTimer.Start();
}
private void dispatcherTimer_Tick(object sender, EventArgs e)
{
VideoControl.Pause();
}

Add this in your dispatcherTimer_Tick-Method:
dispatcherTimer.Stop();
Move the following part into the constructor:
dispatcherTimer = new System.Windows.Threading.DispatcherTimer();
dispatcherTimer.Tick += new EventHandler(dispatcherTimer_Tick);
dispatcherTimer.Interval = new TimeSpan(0, 0, 10);
Make the DispatcherTimer a global variable.
EDIT: Thats how it should look like:
class MyClass
{
private DispatcherTimer _dispatcherTimer; //now your dispatcherTimer is accessible everywhere in this class
public MyClass()
{
_dispatcherTimer = new DispatcherTimer();
_dispatcherTimer.Tick += new EventHandler(dispatcherTimer_Tick);
_dispatcherTimer.Interval = new TimeSpan(0, 0, 10);
}
void PlayClick(object sender, EventArgs e)
{
VideoControl.Play();
_dispatcherTimer.Start();
}
void dispatcherTimer_Tick(object Sender, EventArgs e)
{
_dispatcherTimer.Stop();
VideoControl.Pause();
}
}

Bring the declaration of the timer out into a private class variable, move a couple lines to the constructor of the class, and stop the timer in the Tick handler.
The reason you don't want to keep creating the timer is because there are unmanaged resources involved with a timer and so you're closing that loop.
private dispatcherTimer = new System.Windows.Threading.DispatcherTimer();
ctor
{
dispatcherTimer.Tick += new EventHandler(dispatcherTimer_Tick);
dispatcherTimer.Interval = new TimeSpan(0, 0, 10);
}
void PlayClick(object sender, EventArgs e)
{
VideoControl.Play();
dispatcherTimer.Start();
}
private void dispatcherTimer_Tick(object sender, EventArgs e)
{
dispatchTimer.Stop();
VideoControl.Pause();
}

Try with following code in Tick event:
private void dispatcherTimer_Tick(object sender, EventArgs e)
{
(sender as DispatcherTimer).Stop();
VideoControl.Pause();
}
You can make dispatcherTimer object outside Playclick event and only put Start() method inside PlayClick event in following way:
var dispatcherTimer = new System.Windows.Threading.DispatcherTimer();
public Form1() //// form constructor where you are handling these all event....
{
dispatcherTimer.Tick += new EventHandler(dispatcherTimer_Tick);
dispatcherTimer.Interval = new TimeSpan(0, 0, 10);
}
void PlayClick(object sender, EventArgs e)
{
VideoControl.Play();
dispatcherTimer .Start();
}